In addition to the list @Zoidburg
provided, regular ADA Aqua Soil Amazonia (not just Light and Amazonia II) is a great substrate for Caridina shrimp (plural.) Probably my favorite. Releases enough ammonia to actually cycle a tank properly. Ignore comments about it clouding water. It won't if you aren't sloppy. But what you have should work well for a while if you focus on more ideal water parameters.
How much are you feeding? I asked because a more specific answer is necessary. It's good that it's eaten quickly but how much
? Please be as specific as you can.
Figure out the specific plants you have. Start keeping plants that will work with your setup without using CO2. If you want to keep shrimp and are new to them, that's the only way to go. Maybe do some reading here on the forum about how and why people use pressurized CO2.
Commonly accepted temperature parameters are available all over this forum and countless other websites. How much reading about Crystal Shrimp have you done? Don't take this as being rude - because I'm not trying to shame you - but it seems like you need to do a lot more research. Coming here to ask questions was a terrific first step. Spend at least an hour today reading about proper care. If you don't, your shrimp will continue to die because you've unintentionally created the perfect storm for them.
Could you post photos of your tank to give us an idea of what you're working with?